The present invention relates generally to document handling systems, such as mail sorting systems, and more particularly to a novel deflector device for use in preventing feeding of more than one document at a time from a feeder station to which documents are fed on-edge by a document feed magazine.
Document handling systems are well known in which a plurality of documents, such as mailing envelopes and the like, are supported in stacked on-edge relation on a feed magazine and fed to a feeder station while disposed in generally vertical relation transverse to the feed path of the magazine. The feeder station may include a feeder mechanism having one or more feeder belts which define horizontal coplanar reaches engaged by the forward side of the lead document in the feed magazine. See, for example, U.S. Pat. No. 4,275,875 which is incorporated herein by reference. At lease one of the feeder belts may have one or more openings therethrough which pass a vacuum manifold as the openings traverse the document engaging reach so as to draw the lead document against the belt by suction and feed the document transversely from the feed magazine to a further processing station, such as a read station. The read station may include an optical character reader or bar code reader operative to read sorting indicia on each document, such as an alphanumeric address or bar code, which determines a subsequent sorting sequence.
One problem encountered with prior document handling systems of the aforementioned type is that the feeder mechanism may feed two or more documents simultaneously in side-by-side relation to the read station, or other document processing station immediately downstream from the feeder station. For example, in feeder mechanisms of the type employing a vacuum manifold and one or more horizontal feeder belt reaches operative to engage and feed the leading document from the feed magazine, the next successive document may engage the feeder belts before the leading document is substantially released from the feeder belts. If this occurs, the friction between the feeder belts and the next successive document may cause the second document to be advanced simultaneously with the lead document. Depending on the extend of document overlap, the read station may only read the sort indicia on one of the documents, thereby resulting in incorrect sorting or damage to the documents. As disclosed in U.S. Pat. No. 4,275,875, one manner of addressing this problem is to provide jogger arms which are positioned adjacent the horizontal feeder belt reaches and are actuated in timed relation to passage of the feeder belt suction holes along the vacuum manifold so as to push the whole stack of documents on the feed magazine away from the feeder belts just before the belt suction holes are interposed between the lead document and the vacuum manifold. Movement of the entire stack in this manner frees the leading document for easier separation from the remaining stack.
The present invention provides a further technique for addressing the aforedescribed problems encountered with vacuum belt type document feeders by providing a deflector device operative to deflect the trailing ends of documents being fed on a feed magazine so as to prevent engagement of each successive document with the feeder belts until the prior lead document has been substantially removed from the feeder belts, thereby preventing feeding of more than one document at a time from the feed magazine.